import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MapTest {
    public static void main(String[] args) {
        List<Map<String,Object>> list = new ArrayList<>();
        Map<String,Object> map = new HashMap<>();
        map.put("id", 100);
        map.put("title", 200);
        map.put("size", 300);
        map.put("time" , System.currentTimeMillis());
        list.add(map);
        //向list中存入map,存储的是什么?存储的是map地址;
        System.out.println(map);
    }
}
